The present invention, relates to controlling pieces of equipment by sound pulses.
Various methods exist in the prior art for controlling pieces of equipment by sound pulses, where the sound pulses may be produced by a user by clapping the hands or snapping the fingers.
In U.S. Pat. No. 8,189,430, the user claps the hands in order to select between different commands for a TV set. The control system is based on a receiver having two sound sensors. When the user claps the hands and emits a sound clap, the receiver uses the difference between clap travel times to calculate an angular direction relative to an axis passing halfway between the two sensors. This angular direction serves to determine which command is to be executed by the TV set. That system presents several drawbacks.
Firstly, the sound clap receiver containing the sound sensors is incorporated in the appliance that is to be controlled, such that the sensors are relatively close together, being about one meter apart at most. That particular arrangement and the bandwidth used for the frequency band of the sound pulse require the user to occupy a distance that is more or less fixed (i.e. not too close, not too far away, and substantially directly in front) relative to the piece of equipment that is to be controlled, so that any uncertainty about the angular direction remains reasonable.
Thereafter, performing that method makes it necessary to filter out the noise generated by the piece of equipment being controlled and thus to have knowledge about the characteristics of that noise. Unfortunately, such filtering is ineffective for ensuring that the receivers operate properly in the presence of other sources of disturbing sounds, for example human voices. In practice, when the equipment is used in a home environment, in particular when the equipment is a TV set, it is located in a zone that is noisy.
Furthermore, that system does not make it possible with only two sound claps to select one piece of equipment that is to be controlled from a plurality of pieces of equipment, but only to select one command from two possible commands for that piece of equipment.
That system also does not make it possible to define different commands as a function of the zone in which the sound claps are made.
Likewise, it is not possible to define subzones in which sound claps are not to be taken into account, i.e. do not generate any command, so as to exclude zones from which noise pollution is too great.
Finally, when using two receivers, the number of different commands capable of being generated by two sound pulses is limited to two when using two receivers; in any event, the number of commands cannot be greater than the number of receivers.